A robotic truss builder that was conceived, designed and built by Caltech researchers has successfully built a structure in space—without the help of astronauts—for the first time. The truss builder, part of DARPA’s Novel Orbital and Moon Manufacturing, Materials, and Mass-efficient Design (NOM4D) program, consists of an autonomous manipulator that picks up struts and joints held in nearby dispensers to repeatedly assemble identical sections, or bays, of a perimeter truss.

“This is the first time that a structure has been autonomously constructed in space,” says Sergio Pellegrino, the Joyce and Krent Kresa Professor of Aerospace and Civil Engineering, the Lynn Booth and Kent Kresa Department of Aerospace Leadership Chair, the executive officer for aerospace and a senior research scientist at JPL, which Caltech manages for NASA.

Pellegrino is team leader of Caltech’s Autonomous In-Space Tensioned Reflector Assembly (ASTRA) demonstration, a robotic builder that has spent the last six months in space, working to construct a 1.4-meter-diameter (4.6-foot-diameter) reflector antenna from composite fiber tubes, aluminum joints and a Kapton reflective surface.